[PATCH 6/7] media: dvb-frontends: drx39xyj: Refactor firmware upload

From: Ricardo Ribalda
Date: Thu Apr 11 2024 - 17:19:31 EST


Do not cache the file, instead load it on demand.

This makes smatch a happy parser:
drivers/media/dvb-frontends/drx39xyj/drxj.c:11908 drx_ctrl_u_code() warn: 'fw' from request_firmware() not released on lines: 11877,11886,11896.

Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
---
drivers/media/dvb-frontends/drx39xyj/drx_driver.h | 2 -
drivers/media/dvb-frontends/drx39xyj/drxj.c | 49 +++++++++++------------
2 files changed, 23 insertions(+), 28 deletions(-)

diff --git a/drivers/media/dvb-frontends/drx39xyj/drx_driver.h b/drivers/media/dvb-frontends/drx39xyj/drx_driver.h
index 15f7e58c5a308..2c2fd4bf79ccf 100644
--- a/drivers/media/dvb-frontends/drx39xyj/drx_driver.h
+++ b/drivers/media/dvb-frontends/drx39xyj/drx_driver.h
@@ -33,7 +33,6 @@

#include <linux/kernel.h>
#include <linux/errno.h>
-#include <linux/firmware.h>
#include <linux/i2c.h>

/*
@@ -1910,7 +1909,6 @@ struct drx_demod_instance {
/* generic demodulator data */

struct i2c_adapter *i2c;
- const struct firmware *firmware;
};

/*-------------------------------------------------------------------------
diff --git a/drivers/media/dvb-frontends/drx39xyj/drxj.c b/drivers/media/dvb-frontends/drx39xyj/drxj.c
index 19d8de400a687..1ef53754bc037 100644
--- a/drivers/media/dvb-frontends/drx39xyj/drxj.c
+++ b/drivers/media/dvb-frontends/drx39xyj/drxj.c
@@ -56,6 +56,7 @@ INCLUDE FILES
#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

#include <linux/module.h>
+#include <linux/firmware.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>
@@ -11750,6 +11751,7 @@ static int drx_ctrl_u_code(struct drx_demod_instance *demod,
u8 *mc_data = NULL;
unsigned size;
char *mc_file;
+ const struct firmware *fw;

/* Check arguments */
if (!mc_info || !mc_info->mc_file)
@@ -11757,28 +11759,22 @@ static int drx_ctrl_u_code(struct drx_demod_instance *demod,

mc_file = mc_info->mc_file;

- if (!demod->firmware) {
- const struct firmware *fw = NULL;
-
- rc = request_firmware(&fw, mc_file, demod->i2c->dev.parent);
- if (rc < 0) {
- pr_err("Couldn't read firmware %s\n", mc_file);
- return rc;
- }
- demod->firmware = fw;
-
- if (demod->firmware->size < 2 * sizeof(u16)) {
- rc = -EINVAL;
- pr_err("Firmware is too short!\n");
- goto release;
- }
+ rc = request_firmware(&fw, mc_file, demod->i2c->dev.parent);
+ if (rc < 0) {
+ pr_err("Couldn't read firmware %s\n", mc_file);
+ return rc;
+ }

- pr_info("Firmware %s, size %zu\n",
- mc_file, demod->firmware->size);
+ if (fw->size < 2 * sizeof(u16)) {
+ rc = -EINVAL;
+ pr_err("Firmware is too short!\n");
+ goto release;
}

- mc_data_init = demod->firmware->data;
- size = demod->firmware->size;
+ pr_info("Firmware %s, size %zu\n", mc_file, fw->size);
+
+ mc_data_init = fw->data;
+ size = fw->size;

mc_data = (void *)mc_data_init;
/* Check data */
@@ -11874,7 +11870,8 @@ static int drx_ctrl_u_code(struct drx_demod_instance *demod,
0x0000)) {
pr_err("error reading firmware at pos %zd\n",
mc_data - mc_data_init);
- return -EIO;
+ rc = -EIO;
+ goto release;
}

result = memcmp(curr_ptr, mc_data_buffer,
@@ -11883,7 +11880,8 @@ static int drx_ctrl_u_code(struct drx_demod_instance *demod,
if (result) {
pr_err("error verifying firmware at pos %zd\n",
mc_data - mc_data_init);
- return -EIO;
+ rc = -EIO;
+ goto release;
}

curr_addr += ((dr_xaddr_t)(bytes_to_comp / 2));
@@ -11893,17 +11891,17 @@ static int drx_ctrl_u_code(struct drx_demod_instance *demod,
break;
}
default:
- return -EINVAL;
+ rc = -EINVAL;
+ goto release;

}
mc_data += mc_block_nr_bytes;
}

- return 0;
+ rc = 0;

release:
- release_firmware(demod->firmware);
- demod->firmware = NULL;
+ release_firmware(fw);

return rc;
}
@@ -12271,7 +12269,6 @@ static void drx39xxj_release(struct dvb_frontend *fe)
kfree(demod->my_ext_attr);
kfree(demod->my_common_attr);
kfree(demod->my_i2c_dev_addr);
- release_firmware(demod->firmware);
kfree(demod);
kfree(state);
}

--
2.44.0.683.g7961c838ac-goog